The present invention relates generally to high speed container placement apparatus and more particularly to a high speed container apparatus for use in combination with filling equipment to achieve accurate net weight product filling of the containers.
Government regulations require that the average actual net weight of package or containerized consumer products, such as instant coffee, be equal to or above the labelled net weight of the products. To keep abreast of the demand for their products, manufacturers must utilize high speed filling machines which move the containers at constant speeds. Since only volumetric dispensing devices can be used to fill moving containers and the labelled net weight must be close to the actual net weight even when the dispensed volume or the product density are at their lowest levels, the manufacturers often overfill containers with considerable amounts of product as fluctuations in the density of the product and the dispensing volumes occur.
To eliminate such inaccuracies, the product should be dispensed by weight into the containers; however, accurate weighing requires a low rate of product flow which, in turn, requires long filling cycles. Ideally, to keep the length of filling time to a minimum, the containers can be first underfilled with the bulk of a product from a volumetric filling machine. Thereafter, these underfilled containers can be topped off with a small amount of product to bring the actual net weight to the labelled net weight in fairly short time cycle, e.g., under two seconds, utilizing low product flow in a machine dispensing by weight.
Since weight dispensing devices cannot travel at high speeds and maintain their accuracy utilizing the desirable low product flow rate, it is necessary to perform the top-off dispensing operation from the stationary dispensing devices. This permits an unimpeded flow of product into the stationary dispensing device as well as accurate weight control. With the containers travelling at a desired line speed, the containers must be decelerated to a stop underneath the dispensing device for the period of time necessary for the filling operation to be performed at a low rate of product flow and accelerated to restore them to their normal rate of line speed.
The conventional means employed to perform these deceleration/acceleration steps utilizes a reciprocating mechanism to position the containers under stationary dispensing devices and return them to the conveyor line. However, these mechanisms are incapable of operating in connection with the high line speeds, even if they handle several containers simultaneously, since the mechanisms are large, bulky and require several time-consuming movements for proper positioning and removal of the containers in relation to the dispensing devices.
It is an object of the present invention to provide a novel container placement device for use in conjunction with filling devices which dispense product within a very close tolerance of a desired weight.
A further object is to provide such device which decelerates the containers to a stop from a high line speed for the filling operation and accelerates them afterwards to the full line speed.
It is also an object to automatically handle each container on an individual basis to insure accurate filling by weight thereof.
Still another object is to provide such a device which may be readily fabricated and will enjoy a long life in operation.